The present invention relates to a device with a shaft and with at least one hub attached to this shaft and to a method for manufacturing of this device.
A device of this type is disclosed e.g. in EU-PS 0 521 354. The shaft of this device shows the usual overmeasure with respect to the opening of the hub. The wall opening in the hub has the shape of a cylinder. That one side of the opening in the hub from which the shaft is to be led into the hub is widened, having the shape of a funnel. Otherwise explained, this means that the margin of the opening in the hub is provided with a phase. The inclined wall of this phase has the shape of a cone. If a vertical section is carried out in such a manner that the main axis of the opening is placed in the section plane, then the cut across the phase appears as a straight line. Between said straight line and the equally straight running surface line of the cylindrical opening of the hub, a blunt angle is present.
Said phase facilitates the insertion of the shaft into the hub in such a way that the slanted wall of the phase presses continuously the excessive material of the shaft more deeply into the shaft. That area of the margin of the hub, where said blunt angle is present, acts however as an edge on the shaft. The pressure built up by the compression of the shaft material due to the slanted wall of the phase, grows sudden in the region of said hub edge. As a consequence, material from the shaft surfaces may be torn off by said edge. On the joining surface of the shaft or of the hub resp. which are damaged in this way, the fit of the hub on the shaft is not sufficiently well defined.
It is an object of the present invention is to remove said disadvantage as well as further disadvantages of the prior art.
This object is solved by a device of the afore mentioned type in accordance with the present invention as defined in the characterizing portion of the independent claim 1.